Warp-stop mechanism for textile apparatus and machinery



Aug- 14, 1934- s. A. WELCH Er AL 1,970,264

WARP STOP MECHANISM FOR TEXTILE APPARATUS AND MACHINERY Filed Dec. 8,1932 2 Sheets-Sheet l Aug. 14, 1934. s. A. WELCH ETAL 1,970,264

WARP STOP MECHANISM FOR TEXTILE APPARATUS AND MACHINERY Filed Deo. 8,1932 2 sheets-sheet 2 AHorxess Patented ug. 14, 1934l UNITED STATESWABP-STOP MECHANISM FOR TEXTILE AP- PARATUS AND MACHINERY Sidney ArthurWelch, Albert Fairholme Guyler,

and. William Henry Boaler, Spondon, near Derby, England, assignors toCelanese Corporation of America, a corporation of Delaware ApplicationDecember 8, 1932, Serial No. 646,246

In Great Britain 7 Claims.

This invention relates to Warp-stop mechanisms which, in connection withmachines in which a sheet of Warp threads is used, are designed to stopthe machine on breakage or slackening of any one of the warp threads.The invention is applicable generally to any machine in which a sheet ofwarps is employed, but is especially advantageous in connection withwarp knitting machines.

According to the invention, a warp stop mechanism comprisesreciprocating n'ieans extending and reciprocating across and beneath thewarp threads and adapted to be engaged by a broken warp thread fallingacross it, and to move such thread laterally, and one or more upstandingcontact members e. g. springmounted or pivoted lingers, adapted to bedeflected under the action of a broken thread falling across said meansand by such deection to stop the machine through any suitable medium.Conveniently the stopping of the machine is effected by means of anelectrical stop motion circuit of the usual type,

one or more contact pins being provided with which the upstanding memberor members contact upon being deected, and so complete a circuit to stopthe machine. 0n breakage or undue slackening of any one of the warpthreads, the broken or slack thread falls down and lies across thereciprocating means and is brought thereby into engagement with anupstanding member, in such a manner as to deect it into contact with thestop motion circuit contact pin. The reciprocating member mayconveniently comprise a bar extending across the warps, and havingnotches or serrations, or upstanding portions on the upper edge in orbetween which the broken threads lodge, and are moved laterally with thebar. II the thread does not immediately fall into a notch or serrationin the ban-it will be brushed in by one of the. upstanding memberswhich, on the continued motion of the bar, will be deected. If thethread is brushed in towards the end of a reciprocation of the bar sothat the motion of the bar is not continued, deflection will occurduring the reverse motion of the bar.

It is generally convenient to use a plurality of upstanding members inorder to reduce the amount of motion of the bar, and to make the devicerespond more quickly on breakage of a thread..V Thus, while oneupstanding member will serve for a narrow warp, the provision oi twosuch members reduces the distance through which the reciprocating membermust move to cover the whole width of warps, and enables the frequencyof reciprocation to be increased. Sim- December 22, 1931 ilarly withbroader warps, a proportionate number of members may be used.

In order to increase the certainty of operation of the device,particularly to ensure a good contact when an electric stop motion isused, a plurality of parallel bars e. g. four, may be employed,alternating with one or more sets of contact springs e. g. three, andhaving notches or serrations at the same points along their length.This' arrangement. enables the thread when brought into contact with theupstanding member to be supported on both sides of that member,

and renders the operation of the device morepositive and reliable.

By the provision of the warp stop mechanism according to the invention,it will be seen that no threading up of the Warp threads isnecessitated, the threads operating the stop motion merely upon droppingacross the serrated bar. This renders the textile operations in whichthe warps are concerned very much simpler, and greatly reduces the costof the operations owing to the elimination of the expensive andtroublesome threading up operation. In addition, until breakage orslackening of one of the warp threads occurs, there are no parts withwhich the threads are in; contact and upon which they may be rubbed orworn. Even upon breakage, the broken thread is not submitted to anyundue strain, while at the same time positive electrical contact ismade, to stop the machine.

In order to stop the machine on'contact, any desired electricallyoperated stop mechanism may be used and may be operated by a solenoidmember in circuit with the stop motion circuit, the contact bar and theupstanding member.

The invention will now be described in greater detaill with reference tothe accompanying drawings, but it is to be understood that thisdescription is given by way of example only and is in no respectlimitative.

Fig. 1 is a perspective view of a section of the thread-operated contactmechanisms;

Fig. 2 is a front elevation of Fig. 1;

Fig. 3 shows diagrammatically the application of the stop-motionmechanism to a two-bar warpknitting machine;

.\ Fig. 4 is an alternative detail of Fig. l; and

\\Figs. 5 and 6 show diagrammatically alternative forms of electricindicators whichv may be employed with the stopmechanism according tothe invention. e

As shown in Fig. 1, a series of thin parallel bars 12, (four shown),having dove-tail notches 13 at intervals along their upper edges arespaced apart and secured at their extremity by a common shackle 15 insuch a manner that a notch in any bar is in alignment with thecorresponding notches in the other bars.

A connecting-rod 16, pinned to a rear lug 17 of the shackle 15,transmits longitudinal reciprocating motion to .the bars 12 from asuitable cam or crank, (not shown), the bars 12 being supported onfreely rotatable rollers 18. Situated at a suitable distance beneath,and in alignment with the bars 12 is a stationary bar 19 bearing sets ofupstanding iiexible pins 20, so arranged with respect to the bars 12 asto penetrate the spaces between the bars and toprotrude a suitabledistance above the upper edges of the bars. A further stationary bar 21is situated alongside the bars 12 and carries pairs of stiff pins 22which protrude sideways from the bar and extend beneath the bars 12 at a.short distance from their lower edges.

The bar 21 carries as many pairs of stil pins 22 as there are sets offlexible pins 20 on the bar 19, ,the pins 22 being arranged so as to lieclosely one on each side of the exible pins 20. Wires 24 and 23 formingpart of an electric stop-motion circuit (to be described later), areconnected to the bars 19 and 21 respectively, the circuit remaining openwhile the pins are in the position shown in Fig. 1.

The mounting and operation of the stop-motion can be clearly followed byreference to Figs. 2 and 3. In Fig. 3, warp-beams 30 of a Warp-knittingmachine are rotated through gearing of any suitable type from anelectric motor 31. Warpthreads 32 proceed in sheet form from the warpbeams 30 over tension bars 33 and through guides 34 to the needles 35 ofthe machine.

Situated at a short distance beneath the warp sheets 32 and extendinglaterally across the full width of the sheets are the reciprocating bars12. Upon breakage or undue slackening of any warp thread, the threadfalls from the sheet and lies across the top of the notched bars 12,which by reason of their reciprocation engage the thread in the nearestapproaching set of notches. The dove-tail shape of the notches, combinedwith the motion of the bars 12, lock the thread as shown at 36 in Fig. 3and draw it taut within the notches, across the width of the bars.

The extent of the traverse of the bars 12 is greater than the distancebetween any two sets of pins 20 so that the trapped thread 36 is carriedlaterally against the nearest set of exible pins 20 which are deflectedfrom the vertical and caused to contact with the corresponding sti pin22, as shown on the right-hand side of Fig. 2. The previously mentionedwires 23 and 24 are connected from the bars 19 and 21 to a solenoidacting as a relay in conjunction with a trip-switch, the whole unitbeing enclosed within a switch-box 38 mounted upon the driving-motor 31.

Upon contact being made between the liexible pins 20 and the stii -pins22, the circuit is closed and the trip-switch caused to operate to stopthe motor 31. Contact between the exible pins 20 and the stili' pins 22serving to operate the stop motion, it is necessary that the bar 21 isinsulated from any part of the machine in contact with the bar 19 andthe exible pins 20.

The alternative form of contact device shown in Fig. 4 may replace a setof exible pin 2(l and comprises a pendulum-like member 37, pivoted at 39and having a bob 40. The upper part of the member 37 penetrates thespace between the bars 12, and is engaged by thread caught in thenotches 13 of the bars 12, in asimilar manner to the operation of thepins 20. Upon being forced from the vertical, the lower end of themember contacts with either of the two stiff pins 22 depending on thedirection of reciprocation of the bars 12,y and closes the stop-motioncircuit, thus bringing the machine to rest.

In order that the slack or broken thread may be located quickly onstoppage of the machine, electrically operated indicating means, asshown diagrammatically in Figs. 5 and 6, may be incorporated inthemachine.

In Fig. 5 the contact pins 22 (six pairs shown), are numbered from 1 to6 according to the section of warp threads served by each. Each pair ofpins 22 is connected through a lead common to both (indicated severallyat 45), to one of a series of electric lamps mounted on an indicatorboard 46, and bearing the corresponding section numbers on theirsurfaces. 'I'he flexible pins 20 are connected by a common lead 47.tothe solenoid member within the switch-box 38. A battery 48 is connectedto the solenoid and to the indicator lamps respectively and supplies thenecessary current to the circuit, which normally is maintained open. Oncontact being made between any one, or set, of flexible pins 20 and thecorresponding contact 22 the circuit is completed, and the currentbesides energizing the solenoid member to operate the trip-switch,illuminates the lamp corresponding in number to the contact member inoperation, which lamp remains illuminated so long as the broken or loosethread is held in contact with the flexible pins 20. The number on thelamp indicates the warpsection from which the broken thread has dropped,thus shortening the time which normally would be taken in locating lthethread. On removal of the thread from the notches 13 of the bars 12,thus releasing the deected flexible pins 20, the circuit is opened andthe indicator-lamp ceases to glow. 115

Though the contact pins 22 are supported from a common bar, i. e.' thebar 21, it will be understood that the pins are insulated from eachother in any suitable manner, inf'order to keep the lamp circuitsindependent.

'I'he indicating system shown diagrammatically in Fig. 6 is adapted tosound a warning bell on breakage or` undue slackening of a warp thread.The contact pins 22 suitably insulated from each other are numbered from1 to 6 accord- 125 ing to the section of warp threads served by each.Each pair of pins is connected through a lead common to both (indicatedseverally at 50) to one terminal of a single electric bell 51. Theflexible pins 20 are connected by a common lead 52 to 130 the solenoidmember within the switch-box 38.

A battery 53 is connected to the solenoid, and to the free terminal ofthe bell 51, respectively, and supplies current to the circuit, which,as explained with reference to Fig. 5, isnormally main- 135 tained open.

On contact being made between one, or a. set of ilexible pins 20 and thecorresponding contact 22 the circuit is completed and the solenoidenergized to operate the trip-switch. As the electric 140 bell isincluded in the circuit the current serves also to ring the bell, whichcontinues to ring after the machine has been brought to rest. A seriesof switches 54 mounted one on each of the several leads from the contactpins to the 145 bell, and numbered according to the number of thecontact pins served by the particular lead upon which the switch ismounted, are then withdrawn in turn until the circuit is broken, and thebell stops ringing. The number on the switch 15o breaking the circuitindicates the warp-section from which the broken thread has dropped,thus saving time in searching for the thread. On removal of the threadfrom the notches of the bars 12, the deected pin or pins can againassume a vertical position away from the contact pins 22. On repairingthe thread the switches 54 are again connected and the machine againstarted.

What we claim and desire to secure by Letters Patent isz- 1. Warp-stopmechanism for a textile machine, said mechanism comprising a bar adaptedto be reciproeated, notches on said bar adapted to engage and retain aslack or broken thread, an electrical contact member, movable meansforming a second contact member disposed in close relation to said barand adapted to be deflected by thread caught in and moved laterally bysaid bar so as to engage and complete through said contact member anelectric circuit adapted to operate means for'stopping said machine.

2. Warp-stop mechanism for a textile machine, said mechanism comprisinga bar adapted to be reciproeated, notches on said bar adapted to engageand retain a slack or broken thread, an electrical contact member, ailexible member forming a second contact member disposed in closerelation to said bar and adapted to be deected by thread caught in andmoved laterally by said bar, so as to engage and complete through saidcontact member an electric circuit adapted to operate means for stoppingsaid machine.

3. Warp-stop mechanism for a textile machine, said mechanism comprisinga bar adapted to `be reciproeated, notches on said bar adapted to engageand retain a slack or broken thread, an elctrical contact member, apivoted member forming a second contact member disposed in closerelation to said bar and adapted to be deected by thread caught in andmoved laterally by said bar, so as to engage and complete through saidcontact member an electric circuit adapted to operate means for stoppingsaid machine.

4. Warp-stop mechanism for a textile machine, said mechanism comprisinga plurality of bars disposed in closely-spaced parallel relation as aVunit and adapted to be reciproeated, dove-tail notches in like positionsalong the upper edges of said bars adapted to engage and retain a slackor broken thread and to move said thread laterally, movable pins formingelectrical contact members adapted to extend through the spaces betweensaid bars and to protrude beyond the thread-engaging level of said bars,an electrical contact member arranged on each side of the said movablepins, the lateral movement of the thread being adapted to deect saidmovable pins so that the said pins contact with one of the saidelectrical contact members and thereupon complete the electrical circuitadapted to operate means for stopping said machine.

5. Warp-stop mechanism for a textile machine,

said mechanism comprising abar adapted to be reciproeated, notches onsaid bar adapted to engage and retain a slack or broken thread, aplurality of electrical contact members, electricallyf operatedindicating means in series lwith said contact members, movable meansforming electrical contact members disposed in close relation to saidbar and adapted to be deflected by thread caught in and moved laterallyby said bar, so as to engage and complete through a contact member theelectric circuit adapted to operate means for stopping said machine andsimultaneously to actuaw the indicating means.

6. Warp-stop mechanism for a textile machine,

said mechanism comprising a bar adapted to be,v reciproeated, notches onsaid bar adapted to gage and retain a slack or broken thread, a plu-rrality of electrical contact members, electricallyoperated indicatingmeans respectively in seriesA with said contact members, movable meansforming electrical contact members disposed in close relation to saidbar and adapted to be deected by thread caught in and moved laterally bysaid bar, so as to engage and complete through a contact member theelectric circuit adapted to operate means for stopping said machine andsimultaneously to actuate the respective indicating means.

7. Warp-stop mechanism for a textile machine, said mechanism comprisinga bar adapted to be reciproeated, notches on said bar adapted to engageand retain a slack or broken thread, a plurality of electrical contactmembers, electricallyoperated indicating means in series with pairs ofsaid contact members, movable means forming electrical contact membersdisposed in close relation to said bar 'adapted to be deilected bythread caught in and moved laterally by said bar, so as to completethrough a contact member an electric circuit adaptei to operate meansfor stopping the machine, and simultaneously to actuate the indicatingmeans and means in the electric circuit between each contact member andthe indicating means to enable the circuits to be broken

